This study proposes a pre-evacuation planning model for large scale volcanic disasters that minimises the total evacuation completion time, incorporating three evacuation modes: private vehicles, evacuation buses, and High-Speed Rail(HSR). The road network is transformed into a STEN (Space-Time Extended Network), consisting of four sub-networks - one for each evacuation mode and one for evacuation bus operations - along with dummy nodes representing evacuation completion. The model is applied to a hypothetical network, and its performance is evaluated by comparing the computational results across four scenarios (promotion of carpooling among households, increase in the number of evacuation buses, expansion of link capacity, and expansion of shelter capacity) and a baseline scenario, considering four cases with different evacuation mode availability. The results demonstrate that incorporating multiple evacuation modes reduces evacuation completion time across all scenarios. Notably, where link capacity is expanded, a significant reduction in evacuation completion time is observed.
Miyazaki et al. (Thu,) studied this question.